By: Kelly llanos Santiago Galezo Andres Beltran Juan David Hernández MUSCULAR SYSTEM

MUSCULAR SYSTEM: The muscular system helps make all your daily movements possible, the muscular system works with help of bones.

MUSCULAR SYSTEM: There are 2 types of muscle movement: Involuntary muscles: are muscles that move without your control Example: the heart, the diaphragm, and intestines. Voluntary muscles: are muscles that you can move when you want. For Example: your leg or hand, and face.

CLASSIFICATION OF MUSCLES: Human have 3 kinds of muscle tissue:

SKELETAL MUSCLE 1.Skeletal muscles: are most common muscles, are voluntary and move bones, and joints by tendons. This muscle’s appearance is striated. This muscles work a lot.

Is found in the heart and is involuntary. The tissue of this muscle has striations, and contracts aprox. 70 times per minute every day of your life. CARDIAC MUSCLE

It has a tissue no striated involuntary muscle and is found in many of your internal organs. Smooth muscle

LEVERS The muscular system and the skeletal system work together as a machine. They are divided in levers: - First class lever - Second class lever - Third class lever

LEVERS First class lever: the fulcrum lies between the effort and the load Second class lever: the load lies between the fulcrum and effort force Third class lever: the effort force is between the fulcrum and load

WORKING MUSCLES Movement of body  pairs of skeletal muscles work together, when a muscle of a pair contracts the other muscle relaxes or returns to its original length. Muscles just pulls they do not push When the muscles on the back of the upper leg contracts, they pull the lower leg up and back

WHAT DO MUSCLES NEED: A good muscular system needs: a healthy diet, with some glucose that is the main source of energy for our muscles, not eating so much fats because you can get overweight. Also we have to make exersice, and for people that make too much exercise have to eat food rich in vitamins and sugars.

WHAT DO MUSCLES NEED: Also making exercise  that makes muscles work and helps muscles to be stronger, have elasticity and resistance. This helps bones, because it to strengthens the bones, because of the traction.

SOME DISEASES: Tear: muscle tissue breakdown. Cramp: involuntary spasmodic contraction, affecting the superficial muscles. Sprain: injury caused by moderate damage or total muscle fibers. Muscular dystrophy: degeneration of skeletal muscles. Atrophy: loss or reduction of muscle tissue.

SOME OTHER DISEASES: Hypertrophy: abnormal growth or development of the muscles, in some cases producing serious deformations. However, muscle hypertrophy controlled is an objective of bodybuilding. Polio: commonly known as polio. It is a disease caused by a virus that attacks the central nervous system and causes the nerve impulses are not transmitted and limb atrophy. Myasthenia gravis: a neuromuscular disorder, is characterized by muscle weakness and muscular system has an acidic component.

CHANGES OVERTIME: Overtime muscles change depending on how much they are used. When they are used too much, they become larger, but when they are not used they become smaller.

CHANGES OVERTIME: Skeletal muscles that do a lot of work, tend to became stronger, because of the increase of cells. People who play basketball and soccer have strong bodies, and people that don't exercise have smaller muscles.

HOW MUSCLES MOVE Your muscle need energy to contract and relax. Your blood carries energy-rich cells to your muscle cells, where the chemical energy stored in these molecules is released. Chemical energy is needed for muscle activity. During activity, chemical energy supplied by food is changed into mechanical energy (movement) and thermal energy (heat).

MITOCHONDRIA: Provide the energy a cell needs to make all their activities- in short, they are the power centers of the cell. They are about the size of bacteria but may have different shapes depending on the cell type.

Mitochondria are membrane-bound organelles, and like the nucleus have a double membrane. But the inner membrane is highly convoluted, forming folds called cristae. The cristae greatly increase the inner membrane's surface area. It is on these cristae that food (sugar) is combined with oxygen to produce ATP - the primary energy source for the cell. Muscles have more mitochondria than others body cells.

RESOURCES: Science level green. Mc graw hill. Pp /htm